*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*›››        The SIO2PC Interface›        A Product of Nick Kennedy›› Reviewed by Alan Sharkis› Member, OL' HACKERS A.U.G., Inc.›› I bought a PC clone, a '286 machine,› a couple of years ago when it became› apparent that I would be doing› considerable writing in the next› several years.  I never intended to› give up my Atari, but I needed a› couple of things that showed no signs› of being possible on the Atari. › There was an XEP80 out there, to be› sure, and that would certainly help› me with my writing.  But AtariWriter› 80 had not yet been released, and› there was no way that I could get› decent resolution for 80 columns› without hooking up a monochrome› monitor as well as the beautiful› nineteen inch TV that had served me› as a monitor for so many years.  File› format was another problem.  It would› be difficult to send my written work› to people on Atari disks, even though› I knew that Happy modified 1050s (I› didn't have one) could produce disks› readable on PCs.  I was also so› spoiled by the keyboard on my 800› that I could never get along with the› one on my 130XE, at least not for› quick typing.  The PC seemed to be a› solution.  It could help me write,› and it could also help me with my› Atari.  Heck, null-modeming between› the two machines became second› nature.  I also learned that› telecommunicating in general was more› efficient with the PC, in spite of› the best efforts of Bob Puff.  So,› the two machines are connected› through switchboxes to both my› printer and my modem and through a› null-modem cable with each other.  I› had read of several modifications to› the Atari that seemed to be PC based,› including the TransKey, which I might› still buy, and the SIO2PC, which I› will review here.›› The SIO2PC is the brainchild of Nick› Kennedy, an engineer who uses PCs at› work and has used 8-bit Ataris for a› long time at home.  Nick was always› interested in having machines talk to› each other through the SIO daisy› chain.  Some of his earlier projects› involved creating hardware/software› to allow a couple of Ataris to› network in this way.  But the SIO2PC› goes way beyond that both in its› function and in its utility now and› in the future.›› Essentially, the SIO2PC consists of› files that run on the Atari and on› the PC that allow the PC to become a› "file server" for the Atari.  That's› the software end.  The hardware is› contained in a little box, with two› cables coming out.  One connects into› the SIO daisy chain -- anywhere in› the chain.  There is minimal› electrical drain, so you don't have› to put it in as your first› peripheral.  Mine is connected after› a P: R: Connection and two disk› drives.  The other end plugs into a› serial port on your PC -- any serial› port.  Most PCs come with two of› these (COM1 and COM2), the program› can support up to COM 4 if you have› more ports installed.  Since the› SIO2PC "takes over" the Atari's SIO› operations, you typically run a› special file when you boot up the PC› that blocks most of this from› happening.  That way you can use your› Atari with the PC turned on.  If› there is still a problem, you simply› disconnect the SIO2PC at the Atari› end.  I have this problem when I want› to print from the Atari or use the› Atari with the modem and the PC is› powered down.  I think I'll› investigate a switched Quitopus to› avoid wear and tear on my SIO› sockets.  There is another solution› to the printing problem, but more› about that later.›› A PC, especially a modern one, has a› good deal of memory available.  Nick› Kennedy reasoned that a good chunk of› that memory could be used to hold› ramdisks for the Atari.  Indeed, he› has provided in the software the› means to create up to four such› ramdisks in sizes of 64K, 92K, 143K› or 184K in either single or double› density.  The ramdisks can be› formatted, or you can format them› with any Atari DOS.  I have found› that the largest ramdisk in double› density will not format for double› side with the Sparta X cartridge, but› it seems to do so with the disk-based› Sparta 3.2D.  Perhaps the X› anticipates 360K of disk space. › However, all forms of formatting› (enhanced density works in a single› density ramdisk, as expected) seem to› work.  Once the ramdisks are set up,› you can simply load Atari files into› them and use the PC as a big ramdisk.  › The PC in service to the Atari 8-bit? › Heck, you ain't seen nothin' yet!›› Now, you MIO users out there, kindly› keep still for a moment.  I know you› can do this with the MIO, but this is› one of the exciting parts.  Suppose› you boot your Atari from D1: as you› normally do.  Then you set up a› ramdrive in the PC with the SIO2PC,› say D2:, and format it with  an Atari› DOS, and write DOS files to it.  Then› you turn off the Atari computer AND› D1.  You then give the SIO2PC a› command to create ramdisk 1 and swap› the contents of 1 and 2 (yes,› ramdisks can be swapped, once set› up.)  Now turn on your Atari› computer, and it will boot from› ramdisk 1!  If you use the Sparta X,› Ramdisk 1 need only hold a config.sys› and an autoexec.bat file, although it› can hold considerably more than that. › You can boot your favorite DOS and› your favorite application.  Loading› is faster than from a mechanical› drive, and SIO sounds are mimicked to› let you know what's happening.  You› can even load your favorite DOS into› ramdisk 1 automatically when you› start the SIO2PC program.  How is› this possible?›› I told you at the outset that the› SIO2PC acts as a "file server" for› the Atari.  That means that the› ramdisks supply the files to the› Atari.  But those ramdisks can also› be saved as ramdisk "images" on any› one of your PC's disk drives.  Mine› happens to have a 65Meg hard drive,› nearly full up.  But I have saved› ramdisk images of my Sparta X boot› disk (as described above) and my› Atari DOS 2.5 in the same directory› as the SIO2PC.  You can use the› floppy drives in your PC the same› way.  Mine happens to have high› density drives.  The 5.25" drive can› give me 360K in double density or› 1.2Meg in high density.  The 3.5"› drive can give me 720K in double› density or 1.44Meg in high density. › If I use the last of these formats, I› can save 7-9 ramdisk images per 3.5"› disk, giving me storage for all of my› Atari disks (7 disk files worth) in› one 100 disk filebox.  That's become› the primary reason for my getting the› SIO2PC.  I needed a wall-stretcher› very badly, and this is really› helping.  Also, the time may be fast› approaching when it will be difficult› to get service on Atari drives.  I› know that it's almost impossible to› get service for Indus drives and that› the only 1050s and XF551s you can get› are now used.  With the SIO2PC, you› don't even need to turn on your Atari› drives, which should cut down on› their wear and tear considerably.›› I mentioned a problem with printing› before, and that there would be an› additional solution in this review. › Here it comes.  Suppose you want to› print a file from your Atari.  Say› you have a word processor running and› you need to print to a printer that› is connected to your PC.  No problem! › In fact, several potential problems› are eliminated.  You simply ask› SIO2PC to go into "print-through"› mode.  It will then take the output› of your Atari and direct it to the› PC's screen, printer, or a PC disk› file.  The program will ask if you› want the Atari's EOL characters› (ASCII 155) changed to carriage› returns, and you'll probably say yes,› because ASCII 155 in the extended IBM› graphics is a cent sign, hardly a› combined line feed and carriage› return.  You'll then be asked if you› want to add line feeds.  The answer› to this depends on how your printer› is set up.  I need to say yes, or to› reconfigure the printer.  It's easier› to say yes.  Finally, the program› asks if you want the eighth bit› stripped.  Those of you who don't› know what that means will soon find› out!  Should your Atari file contain› graphics characters or even inverse› characters, they will not print› normally when in print-through mode. › They _WILL_ give you the IBM graphics› characters (which will probably be› entirely inappropriate) or headaches› in the form of printer control codes› that will really mess up your work. › The easiest solution is to simply› strip the eighth bit, which converts› all of the characters to normal ones. › I have a printer that works in either› IBM or Epson emulation, and I make› sure it's set for Epson.  It's› possible that inverse alphabetics on› the Atari will give me italics in› print-through, but I haven't tried it› yet.  I have printed Atari files› through to my printer with the eighth› bit stripped, and to the PC's screen› as well.  I get nice 80-column screen› displays if the Atari text files are› set up that way.›› There are, of course, several› improvements I would like to see in› the SIO2PC, but they concern areas at› the PC end, and are probably best› addressed through software› improvements.  However, these› improvements will likely be dependent› on each PC user's configuration and› the DOS he or she is using.  For› example, I would like the SIO2PC to› be capable of using expanded or› extended memory, although I› personally would not do that with my› system.  I would also like the› program to tell me how much room is› left on my PC's floppy disk when it› tells me the names of files I have› already placed there.  Otherwise I› have to estimate and sometimes miss. › That means resaving the ramdisk image› on a new, hopefully preformatted› floppy and erasing the partial save› on the old one with DOS after exiting› the program (inconvenient, but not› tragic).  At the Atari end, I'd like› to see a positive shutoff of the› device without plugging and› unplugging connectors, as I described› earlier.›› There are a variety of operations› possible with the program that I have› not talked about because I don't› personally use them.  For example,› there is a status line displayed at› the bottom of the PC's screen that› tells you what SIO2PC is doing. › Because of the way this line writes› to the screen, it can cause problems› with some PC displays, so there is a› way to take it out.  The COM port› number can be changed.  Sometimes a› particular user's system needs the› data line locked on, and this can be› set from the software.  Usually it's› in auto mode.  If you have unusual› addresses for the COM ports or wish› to use one higher than 4, there is a› way to set that address.  Ramdisks› can be uninstalled, just as they are› installed, so that more memory is› freed up for others.  There is a file› included that lets you check your bus› timings and then you have the ability› to alter them.  Most of the time,› however, this is not necessary. › There is also a file that tells you› what COM ports your machine comes› with and what their addresses are (in› case you don't know).  One last file› lets you convert PC files into Atari› ramdisk images.›› There are also lots of nice files› that can run on the Atari, including› one that you run from Atari DOS that› lets you control SIO2PC functions› from the Atari.  I tried it, and it› works, but I have my two machines› sitting side-by-side, so I don't use› it.  Another lets you convert Atari› files into PC files instead of Atari› disk images.  I haven't tried it yet,› but it should be useful in some› applications.  › Nick Kennedy claims that this project› is simply a hobby for him, and that› he has constructed only about fifty› of the units (mine included) and› really wants to get away from that› aspect of it.  Therefore, he has› provided three routes for those who› want the SIO2PC.  You can, of course,› get a fully assembled and tested unit› from him.  You can also download the› files, which are on many systems as› shareware, and either buy a kit of› materials from him using the files to› help you construct it, or you can› simply go out with the list of› materials in the files, purchase the› parts, and hardware-hack to your› heart's content.  Mr. Kennedy› suggests a shareware contribution for› the files, and charges $35.00 for a› kit, and $49.95 for a fully assembled› and tested unit ($2.00 more if you› need a DB25 connector at the PC end› instead of a DB9).  Postage and› handling for both kits and assembled› units is $5.00.  Mr. Kennedy accepts› money orders only at this time.  He› offers full money-back guarantees and› upgrades at $5.00.  His address is:››      N. R. Kennedy›      300 S. Vancouver›      Russellville, AR 72801›› Note:  I read a message on FidoNet's› Atari 8-bit echo from a somewhat› dissatisfied user of the SIO2PC named› David Reed.  Some of David's points› are valid; some I cannot verify.  For› example, David Reed claims that his› copy of the software came complete› with a virus.  Nick Kennedy is› sending out software with a› disclaimer about viruses and he puts› a file-size message on the screen as› a primitive virus-check.  If you are› the owner of a PC, you should have a› virus-checker and use it while any› new software is still on floppy.  I› used mine, and found the files to be› virus-free.›› (ALAN graciously invited members of› OL'HACKERS to his home in November for› a MINI-MEETING, and to demo his SIO2PC› as a good way to learn what equipment› is around, and useful for the 8 BIT.› THANKS ALAN! EDITOR)› ›  *+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*›